CN117642289A

CN117642289A - Laminate and 3D printer

Info

Publication number: CN117642289A
Application number: CN202280045327.3A
Authority: CN
Inventors: 阿莫斯·戈特利布
Original assignee: Weixi Metrology Co ltd
Current assignee: Weixi Metrology Co ltd
Priority date: 2021-06-24
Filing date: 2022-06-24
Publication date: 2024-03-01
Also published as: WO2022272134A1; CA3216617A1; EP4359214A1

Abstract

Laminates useful as windows in 3D printers are disclosed. The laminate includes three or more polymeric layers including upper and lower layers comprising a fluoropolymer (e.g., tetrafluoroethylene) and an intermediate layer comprised of a non-elastomeric polymer (e.g., a polymer of 4-methyl-1-pentene).

Description

Laminate and 3D printer

Cross Reference to Related Applications

The present application claims priority from U.S. provisional application 63/214,265 filed by Amos Gottlieb at 24, 6, 2021.

The present application relates to U.S. provisional application number 62/950,072, filed on 12 months 18 in 2019, and international application number PCT/US 20/66152, filed on 12 months 18 in 2020, claiming priority from U.S. provisional application number 62/950,072. The entire contents of each of U.S. provisional application No. 62/950,072, U.S. provisional application No. 63/214,265, and International application No. PCT/US20/66252 are incorporated herein by reference for all purposes.

Technical Field

The present invention relates to novel polymer laminates and 3D printers using these novel laminates.

Background

Several types of 3D printers use films or sheets with the desired permeability characteristics. Some types of 3D printers, such as CLIP printers (CLIP is an abbreviation for continuous liquid interface production (Continuous Liquid Interface Production) or continuous liquid interface printing (Continuous Liquid Interface Printing)), DLP printers (digital light projector or digital light processor based 3D printers), DLV printers (digital light valve based 3D printers) and some SLA 3D printers, require or may benefit from the use of oxygen permeable films or sheets. Some other types of 3D printers may benefit from or require the use of a film or sheet that may be, but is not necessarily, oxygen permeable. For a description of some 3D printers, reference may be made to U.S. patent nos. 9,200,678, 9,211,678, 9,636,873, 9,486,964, and 10,016,938, the entire contents of which are incorporated herein by reference for all purposes.

International application No. PCT/US 20/66152 discloses a laminate consisting of two layers, namely

(1) A first layer which transmits light and is composed of a first polymer composition which is a single polymer or a mixture of polymers, at least one of which is preferably a non-elastomeric polymer and preferably has a glass transition temperature of at least 0 ℃, such as a PMP polymer as defined in International application, and

(2) A light transmissive second layer adhered to the first layer and composed of a second polymer composition which is a single polymer or a mixture of polymers, at least one of which is a fluoropolymer as defined in the international application.

The laminate may also contain a thin primer layer between the first and second layers.

International application No. PCT/US20/66252 also discloses a method of manufacturing such a bilayer laminate, and the use of such a bilayer laminate as a window in a 3D printer.

Disclosure of Invention

It has been found that if a bi-layer laminate as disclosed in international application No. PCT/US 20/66152 is heated to a relatively high temperature, for example a temperature of more than 80 ℃, or more than 90 ℃, for example up to 100 ℃, during use of the laminate as a window in a 3D printer, the laminate may deform. For example, the laminate may form wrinkles in at least the fluoropolymer layer that provides the upper surface of the window. This is a significant problem, as it is highly desirable that the window remain planar during use of the 3D printer, particularly when the printer is a DLP or SLA printer. This problem may occur, for example, when the resin delivered to the upper surface of the window is an exothermic resin, particularly when the resin is delivered rapidly. The present invention provides a solution to this problem.

In a first aspect, the present invention provides a laminate comprising

(1) An upper layer which (a) transmits light and (b) is composed of an upper layer polymer composition which is a single polymer or a mixture of polymers, at least one of which is a fluoropolymer as defined hereinafter, the upper layer preferably having an oxygen permeability of at least 100 Barrer;

(2) An intermediate layer having a first surface, the intermediate layer (a) being adhered to the upper layer, (b) transmitting light and (c) being comprised of an intermediate polymer composition which is a single polymer or a mixture of polymers, at least one of which is preferably a non-elastomeric polymer and preferably has a glass transition temperature of at least 0 ℃, such as a PMP polymer as defined hereinafter, and

(3) A lower layer that (a) adheres to a second opposing surface of the intermediate layer, (b) transmits light, (c) is comprised of a lower layer polymer composition, and (D) inhibits or prevents deformation of the upper layer when the laminate is heated during its use as a window in a 3D printer, the lower layer polymer composition being a single polymer or a mixture of multiple polymers. The lower layer preferably has an oxygen permeability of at least 100 Barrer.

The terms "upper layer" and "lower layer" are used herein to help define the laminate. As described further below, in one embodiment of the invention, each of the upper and lower layers is comprised of a composition that is a single polymer or a mixture of multiple polymers, at least one of which is a fluoropolymer as defined below; in this case, the upper or lower layer may provide a surface to which the resin is delivered. The upper layer composition and the lower layer composition may be the same. If the underlying composition is not composed of a single polymer or a mixture of polymers, at least one of which is a fluoropolymer as defined hereinafter, the upper layer must be the layer to which the resin is delivered in the 3D printer.

The laminate may also include a primer layer between the upper layer and the middle layer and/or between the middle layer and the lower layer.

The laminate may also contain other layers that do not adversely affect the properties of the laminate.

In its second aspect, the present invention provides a device comprising a laminate according to the first aspect of the invention. The apparatus may be a 3D printer for preparing an article of the desired configuration, the apparatus comprising

(1) A photopolymerizable polymer composition comprising a polymeric material and a polymeric material,

(2) A window having an upper surface and an opposite lower surface, preferably a planar window,

(3) Means for delivering a polymer composition onto or adjacent to the upper surface of the window, an

(4) Means for protecting a pattern of light onto a lower surface of the window, the pattern corresponding to a part having a desired configuration, and the window being transparent to light,

whereby, when the device is in operation, the polymer composition is photopolymerized on or adjacent to the upper surface of the window and forms a part corresponding to the part having the desired configuration,

wherein the window comprises a laminate according to the first aspect of the invention.

In a third aspect, the present invention provides a method of making the novel laminate of the first aspect of the present invention.

Drawings

The invention is schematically illustrated in the drawings, in which

Figure 1 is a cross-sectional diagrammatic view of a portion of the laminate of the present invention,

FIG. 2 is an enlarged view of a portion of FIG. 1;

fig. 3 is a cross-sectional diagrammatic view of a 3D printer.

Fig. 4 is a cross-sectional diagrammatic view of a different 3D printer (e.g., DLP 3D printer); the 3D printer uses a cylinder containing a liquid photopolymerizable resin, and the bottom of the cylinder has a window composed of a transparent oxygen permeable material.

Detailed Description

In the foregoing summary, the following detailed description, examples, and claims, as well as the accompanying drawings, reference is made to specific features of the invention. The features may be, for example, components, compositions, elements, devices, apparatus, systems, groups, ranges, method steps, test results, and instructions (including program instructions).

It should be understood that the present disclosure in this specification includes all possible combinations of such specific features. For example, when a particular feature is disclosed in the context of a particular aspect or embodiment of the invention, or a particular claim, or a particular drawing, that feature may also be used in combination with and/or in the context of other particular aspects, embodiments, claims, and drawings, and is generally used in the invention, except where the context excludes such possibility.

The invention disclosed herein and the claims include embodiments not explicitly described herein and may, for example, use features not explicitly described herein but which provide the same, equivalent or similar functionality as the features explicitly disclosed herein.

The term "comprising" and grammatical equivalents thereof are used herein to mean that in addition to the explicitly recited features, other features are optionally present. For example, a composition that "comprises" (or "that" comprises ") component a, component B, and component C may contain only component a, component B, and component C, or may contain not only component a, component B, and component C, but also one or more other components; or "comprising" (or "comprising") component a, component B and component C may contain only component a, component B and component C, or may contain not only component a, component B and component C, but also one or more other components.

The term "consisting essentially of … … (consisting essentially of)" and grammatical equivalents thereof are used herein to mean that there may be other features not materially changing the invention as claimed in addition to the features explicitly recited.

The term "at least" followed by a number is used herein to denote the beginning of the range starting with that number (which may be a range with or without an upper limit, depending on the variable defined). For example, "at least 1" means 1 or more than 1, and "at least 80%" means 80% or more than 80%.

The term "at least one of the two or more specified components" is used herein to mean either a single one of the specified components or any combination of two or more of the specified components.

The term "at most" followed by a number is used herein to denote the end of the range ending in that number (which may be a range having 1 or 0 as its lower limit or a range not having a lower limit, depending on the variables defined). For example, "at most 4" means 4 or less than 4, and "at most 40%" means 40% or less than 40%, which means a range whose lower limit is the first number and whose upper limit is the second number when the given range is "(first number) to (second number)" or "(first number) - (second number)". For example, "from 8 to 20 carbon atoms" or "8-20 carbon atoms" means a range whose lower limit is 8 carbon atoms and whose upper limit is 20 carbon atoms. The terms "multiple" are used herein to refer to two or more features.

When a method comprising two or more defined steps is referred to herein, the defined steps can be performed in any order or simultaneously (except when the context excludes this possibility), and the method can optionally comprise one or more other steps performed before any one of the defined steps, between two of the defined steps, or after all of the defined steps (except when the context excludes this possibility).

When reference is made herein to "first" and "second" features, this is typically done for identification purposes; the first and second features may be the same or different unless the context requires otherwise, and reference to the first feature does not imply that the second feature is necessarily present (although it may be).

When reference is made herein to "a/an" feature, this includes the possibility of having two or more such features (except when the context excludes such a possibility). Thus, there may be a single such feature or a plurality of such features. When two or more features are mentioned herein, this includes the possibility of: the two or more features are replaced by a fewer or greater number of features providing the same function (except when the context excludes this possibility).

The numbers given herein should be construed as being in a range appropriate for their context and expression; for example, each number is subjected to a variation depending on the accuracy with which it can be measured by methods conventionally used by those skilled in the art at the date of filing of this specification.

The term "and/or" is used herein to mean the existence of the potential set forth before and after "and/or". These possibilities may be, for example, components, ingredients, elements, devices, apparatuses, systems, groups, ranges, and steps.

For example

(i) "item A and/or item B" disclose three possibilities, namely (1) item A only, (2) item B only, and (3) both item A and item B are present, and

(ii) "item A and/or item B and/or item C" discloses seven possibilities, namely (1) only item A present, (2) only item B present, (3) only item C present, (4) both item A and item B present but item C absent, (5) both item A and item C present but item B absent, (6) both item B and item C present but item A absent, and (7) all of item A, item B and item C present.

When the specification refers to a "component selected from the group consisting of … … two or more specified sub-components," the selected component may be a single one of the specified sub-components or a mixture of two or more of the specified sub-components.

According to 35usc 112, if any element in a claim is intended as a means or step combination in the claims without detailing a structure, material, or act supporting it in the claims, it is therefore to be construed as covering the corresponding structure, material, or act described in the specification and equivalents thereof, then the corresponding structure, material, or act under consideration includes not only the corresponding structure, material, or act explicitly described in the specification and equivalents of such structure, material, or act, but also such structure, material, or act and equivalents of such structure, material, or act as described in the U.S. patent document incorporated by reference. Similarly, if any element in a claim of the present application (although the term "means" is not explicitly used) is properly interpreted as being equivalent to a term means or step for performing the specified function, without the recitation in the claim of a structure, material or act supporting it, the corresponding structure, material or act being considered to include not only the corresponding structure, material or act as explicitly described in the specification and the equivalents of such structure, material or act, but also such structure, material or act and equivalents of such structure, material or act as described in the U.S. patent document incorporated by reference.

All documents mentioned herein, as well as all documents filed concurrently with or previously filed in connection with this specification, including but not limited to such documents which are publicly available to the public with this specification, are incorporated by reference into this specification.

The term "fluoropolymer" is used herein to denote (as in the international application) an amorphous polymer comprising units derived from monomers containing at least one fluorinated carbon atom, preferably at least one perfluorinated carbon atom, such as one or more of the following: (i) monomers that are perfluorinated ethylenically unsaturated hydrocarbons, such as tetrafluoroethylene, and/or (ii) perfluoromethyl vinyl ether, and/or (iii) one or more monomers containing a perfluorinated dioxole moiety, including but not limited to perfluoro-1, 3-dioxole, and/or (iv) monomers containing a partially fluorinated or perfluorinated dioxole, dioxane, or other 5-or 6-membered heterocycle. Such heterocyclic monomers may contain an exocyclic double bond or an endocyclic double bond. The fluoropolymer may be a homopolymer or copolymer, including polymers containing units derived from two or more (e.g., three) different monomers, examples of which may be used are (i) perfluoro-2, 2-dimethyl-1, 3-dioxole, (ii) perfluoro-1, 3-dioxole, (iii) perfluoro-1, 3-dioxole, (iv) perfluoro-2, 2-bis-methyl-1, 3-dioxole, (v) 2, 4-trifluoromethyl-5-trifluoromethoxy-1.3-dioxole, (vi) perfluoro-2-methylene-4-methyl-1, 3-dioxole, (viii) perfluoro-2, 2-dialkyl-1, 3-dioxole, (viii) 2.2-bis (trifluoromethyl) -4, 5-difluoro-1, 3-dioxole, (ix) 2.2-bis (trifluoromethyl) -4-trifluoro-1, 3-dioxole, and (x) one or more of which may contain one or more members. Monomers from which fluoropolymers may be derived include those disclosed in U.S. patent 9,643,124B2 and references therein. These and other fluoropolymers are disclosed in US 4,399,264, US 4,935,477, US 5,286,283, US 5,498,682, US 5,008,508 and US 9,643,124B2, the entire contents of which are incorporated herein by reference for all purposes.

Examples of commercially available perfluoropolymers include those sold under the trade names Teflon AF 1100, teflon AF 1300, teflon AF2400, teflon AF 1600, and Hyflon AD.

The term "PMP polymer" is used herein (as in the international application) to denote a polymer containing units derived from 4-methyl-1-pentene. The PMP polymer preferably comprises at least 80 mole%, for example about 100 mole%, of repeat units derived from 4-methyl-1-pentene. The PMP polymer may be a copolymer of 4-methyl-1-pentene and a monomer containing functional units, such as functional units that improve adhesion of the middle layer of the laminate to the upper and lower layers or to the primer when the laminate includes one or more primer layers. Such copolymers are disclosed, for example, in US 7,524,913 (publication No. 2008 0021172), the entire disclosure of which is incorporated herein by reference for all purposes.

Examples of commercially available PMP polymers include those sold under the trade names MX 004, MX 0020, MX 002, R-18 and DX 485.

An upper layer and a lower layer of the laminate.

Each of the upper and lower layers of the laminate is composed of a polymer composition comprising a single polymer or a mixture of multiple polymers. The upper and lower layers may be the same or different. For example, the upper and lower polymer compositions may be the same or different, and/or the thickness of the upper and lower layers may be the same or different.

In one embodiment, each of the upper layer composition and the lower layer composition comprises a polymer or a mixture of polymers comprising a fluoropolymer as defined above. In this case, the thickness of the upper and lower layers is preferably the same or similar such that when the laminate is heated when used in a 3D printer, the laminate remains substantially planar without wrinkling any of the fluoropolymer layers. In this embodiment, any of the fluoropolymer layers may provide a surface to which the polymer composition is delivered when the laminate is used in a 3D printer.

In other embodiments, the lower layer composition (a) comprises a polymer or mixture of polymers that does not comprise a fluoropolymer as defined above, and (b) preferably has a thickness such that the lower layer prevents deformation of the upper layer when the laminate is heated when it is used in a 3D printer.

The thickness of each of the upper and lower layers of the laminate is preferably 0.5-500 μm, such as 1-100 μm, such as 5-25 μm.

An intermediate layer of the laminate.

The intermediate layer of the laminate is composed of an intermediate polymer composition which is a single polymer or a mixture of polymers, at least one of which is preferably a non-elastomeric polymer and preferably has a glass transition temperature of at least 0 ℃. In one embodiment, the intermediate polymer composition comprises a PMP polymer as defined hereinbefore; in this embodiment, the intermediate composition may consist essentially of a homopolymer or copolymer of 4-methyl-1-pentene. In other embodiments, the intermediate layer is composed of a polymer composition that does not include a PMP polymer, such as a polymer composition that includes: polyesters (such as Mylar), poly (2, 6-diphenyl-p-phenylene ether), CMSM (such as described by Xiao-Hau, gas Separation Membranes [ gas separation membranes ], adv poly.materials [ advanced high molecular materials ]. 2018), polyacetylenes, para-substituted polystyrenes, or polynorbornenes (such as poly (trimethylsilylnorbornene)).

The thickness of the intermediate layer may be, for example, 0.25 to 5 mils, such as 0.75 to 2 mils. The oxygen permeability of the first layer is preferably at least 10Barrer.

Primer layer.

The laminate optionally includes a primer layer between the upper layer and the intermediate layer and/or a primer layer between the lower layer and the intermediate layer. The primer layer or layers, if present, need not be continuous, but may be, for example, a series of lines, a rectangular pattern, or a series of droplets in a regular or irregular pattern.

The primer is preferably a compound comprising functional groups that can interact with one or both of the adjacent layers. Thus, the primer may include a fluorinated portion that promotes adhesion to one of the fluoropolymer-containing layers and/or another portion that promotes adhesion to the laminate interlayer. The primer compound may for example be a fluoropolymer as defined containing one or more functional groups, such as carboxyl groups. The presence of one or more perfluorocarbon atoms in the primer aids in adhesion to the second (fluoropolymer) layer and the presence of suitable functional groups, such as terminal and/or pendant carboxyl or phosphate groups, aids in adhesion to the intermediate layer, which may, for example, comprise a PMP polymer. Suitable primers include dicarboxy- (poly-perfluoro-2, 3-dimethylene-1-oxolane), copolymers of perfluoroethylene and perfluoro-2, 2-bis-methyl-1, 3-dioxole having terminal and/or pendant carboxylic acid groups or phosphate groups, fluor PMP polymers (as solutions in solvents), olink AD1700, fluorolink phosphate, fluorolink MD 700, and amide terminated Fluorolink.

The primer may be applied to the surface of the preformed film of the intermediate polymer composition, for example as a solution of the primer in a solvent that is subsequently removed completely or almost completely, thereby forming a thin layer of primer compound on the surface of the film. The amount of solvent remaining in the layer is preferably less than 5%, in particular less than 2% by weight of the primer layer. The primer may be applied as a solution (e.g., a contained solution) in a fluorinated solvent (e.g., fluorinert or novock) containing, for example, 0.5% -5% by weight of the primer. The primer solution may be applied in any manner, such as by an ultrasonic spray nozzle or by manual application. The dried primer layer is very thin and may, for example, have a thickness of about 10nm to about 5 μm. The primer layer is very thin and the primer may have an oxygen permeability of greater than 10Barrer, typically greater than 50Barrer, and in some cases up to 3000 Barrer.

Transparency of the laminate.

Many 3D printers rely on photopolymerization of a resin when the resin is exposed to light having a particular wavelength. The wavelengths currently used are about 385nm, about 405nm and about 420nm, but other wavelengths will probably be employed in the future. The laminate should be sufficiently transparent, preferably substantially transparent, to the wavelength used to photopolymerize the resin.

A method of making a laminate.

A preferred method of manufacturing a laminate according to the first aspect of the invention is described herein. The method preferably employs activation of both sides of a preformed film comprised of an intermediate polymer composition (e.g., containing a PMP polymer) and application of a primer solution to both sides of the preformed film. Activation may, for example, include exposing both surfaces of the film to corona etching and/or plasma etching, followed by application of a primer solution to both surfaces of the preformed film, while an activation effect is also present. A solution of the upper layer polymer composition (comprising the perfluoropolymer) is coated on the first surface of the preformed film and then heated to remove the majority of the solvent, creating a hard layer of the upper layer composition on the first surface of the preformed film. After the first surface is coated and the coating on the preformed film is sufficiently hard for treatment, a solution of the underlying polymer composition (comprising the perfluoropolymer) is coated on the opposite surface of the preformed film and then heated to remove the majority of the solvent to produce a hard layer of the underlying composition on the second surface. In the final step, the product is placed in a vacuum oven.

In another embodiment, the laminate according to the first aspect of the invention is prepared by the steps of: (A) Providing a preformed film comprising an intermediate polymer composition; (B) Activating both surfaces of the preformed film and/or applying a primer composition to both surfaces of the preformed film; (C) Providing two preformed films, one comprising an upper layer polymer composition and the other comprising a lower layer polymer composition, and (D) adhering one of the films to one surface of the preformed film and the other of the films to the opposite surface of the preformed film.

In another embodiment, the laminate according to the first aspect of the invention is prepared by: providing a preformed film of the intermediate composition; coating a liquid composition comprising an upper layer polymer composition on one surface of the preformed film and coating a liquid composition comprising a lower layer polymer composition on the opposite surface of the preformed film; and curing the liquid composition on the preformed film. Optionally, one or both surfaces of the preformed film may be activated and/or provided with a liquid primer composition that is dried prior to the upper and lower polymer liquid compositions, prior to the application of the liquid composition comprising the upper and lower polymer compositions to the preformed film.

In another embodiment, the laminate is prepared by a method comprising the steps of:

(A) Installing a roll of preformed film comprising an intermediate polymer composition into a web coater;

(B) Subjecting both surfaces of the preformed film to an activation step, followed by coating both surfaces with a liquid primer composition, followed by drying the liquid primer composition;

(C) Applying a solution comprising an upper layer polymer composition to one surface of the preformed film from step (B), and then drying the solution until it is no longer tacky; and

(D) Applying a solution comprising an underlying polymer composition to the opposite surface of the preformed film from step (C), and then drying the solution until it is no longer tacky.

Steps (C) and (D) may be repeated until a desired thickness of the dried polymer composition is achieved. The coated film may then be placed in a vacuum oven and heated to remove any residual solvent.

In another embodiment, the laminate is prepared using an extrusion line capable of coextruding two or more polymer compositions. There is one hopper and extruder barrel for the intermediate polymer composition, and a hopper and extruder barrel for each of the upper and lower polymer compositions. Each of the polymer compositions was loaded into its hopper and a laminate having a middle layer composed of the middle polymer composition, a top layer composed of the upper polymer composition, and a bottom layer composed of the lower polymer composition was extruded.

A 3D printer using the novel laminate of the first aspect of the invention.

The laminate of the first aspect of the invention may be used in any 3D printer to provide a window on which to deposit a polymer composition. In some 3D printers, the laminate preferably has oxygen permeability; in other 3D printers, however, the laminate need not have (although it may have) oxygen permeability. The novel laminate is particularly useful in 3D printers, where the window can be heated to a fairly high temperature, for example above 80 ℃ or above 90 ℃, for example about 100 ℃. Such heating may occur when the polymer composition deposited on the window comprises an exothermic resin (e.g., a resin that generates heat when it cools, such as an acrylate resin). Such resins are sometimes used in SLA 3D printers.

Example 1.

Each side of the film of 1 mil poly (4-methyl-1 pentene) was treated with a corona etcher and then a thin layer of primer in the form of a 1% solution of dicarboxyl- (polyperfluoro-2, 3-dimethylene-1-oxolane) in Fluorinert FC-40 was sprayed using an ultrasonic sprayer. The oxacyclopentane solution was spread evenly on both surfaces of the PMP film and then dried. Then using Teflon ^TM A solution of AF2400 in Fluorinert coated the top surface of the PMP film. The resulting product was cured at 80 ℃. Then using Teflon ^TM The solution of AF2400 coats the bottom surface of the PMP film. The resulting product was first cured at 80 ℃ and then in vacuo at elevated temperature. The layers in the resulting film cannot be separated by hand.

Example 2.

Each side of the 2 mil PMP film was corona etched and then sprayed with a thin layer of a solution containing a primer that was a copolymer of perfluoroethylene and perfluoro-2, 2-bis-methyl-1, 3-dioxole having terminal and/or pendant carboxylic acid groups. The solution was then dried. The primer layer has an oxygen permeability of greater than 10 barrers, typically greater than 50 barrers, and in some cases up to 3000 barrersDegree. Drying the sprayed coating, and then using Teflon ^TM The solution of AF2400 coats one side of the film. The product was cured at 80 ℃. Then using Teflon ^TM The solution of AF2400 coats the second side of the film. The product was cured at 80 ℃. The resulting product is subjected to final curing in vacuo at elevated temperature. The layers in the resulting film cannot be separated by hand. This is an example of using a primer having an oxygen permeability of greater than 10Barrer.

Example 3.

Example 2 was repeated substituting a copolymer of perfluoroethylene having terminal phosphate groups and perfluoro-2, 2-bis-methyl-1, 3-dioxole for the "copolymer of perfluoroethylene having terminal and/or pendant carboxylic acid groups and perfluoro-2, 2-bis-methyl-1, 3-dioxole".

Example 4.

Example 2 was repeated substituting SF60 (a polymer produced by kemu company (Chemours)) for "copolymer of perfluoroethylene and perfluoro-2, 2-bis-methyl-1, 3-dioxole having terminal and/or pendant carboxylic acid groups".

Example 5.

Example 2 was repeated substituting EVE-P (monomer produced by Cormu Co.) for "copolymer of perfluoroethylene and perfluoro-2, 2-bis-methyl-1, 3-dioxole having terminal and/or pendant carboxylic acid groups".

Example 6.

The laminate prepared as described in example 2 was mounted in a tray of a 3D printer. Several 3D prints were made and observed with monolithic Teflon ^TM The 3D prints made with AF2400 films were not significantly different from those made with the laminates prepared according to example 2. When using monolithic Teflon ^TM The printer speed, resolution, and pull were the same when using the AF2400 film and when using the laminate prepared according to example 2.

Example 7.

The laminate prepared as described in example 2 was mounted in trays of different 3D printers, several 3D prints were made, and it was observed that the entire Teflon was used ^TM 3D printed matter manufactured by AF2400 film and applicationThere were no significant differences in those made from the laminates prepared according to example 2. When using monolithic Teflon ^TM The printer speed, resolution, and pull were the same when using the AF2400 film and when using the laminate prepared according to example 2.

Example 8.

Each side of the polyester film was corona etched and then sprayed with a thin layer of dicarboxy- (polyperfluoro-2, 3-dimethylene-1-oxolane). The sprayed layer is then dried. The upper and lower sides of the product were then successively subjected to Teflon ^TM Solution coating of AF 2400. Each side of the film was cured at 80 ℃ and the resulting product was cured in vacuo at elevated temperature. The layers in the resulting film were found to adhere so firmly to each other that they could not be separated by hand. This is an example of making a membrane that does not have an oxygen permeability of at least 10Barrer.

Additional information about the present invention is as follows.

The present invention addresses the need for a light and oxygen permeable material to be used in a tray or build area (also referred to as a build plate or build assembly) of several types of 3D printers. It also addresses the need for optically transparent materials in trays or build areas to be used in 3D printers, which require non-stick properties but may not require oxygen. In both cases, the light transmissive laminate of the present invention consists of at least three layers, wherein at least the upper layer, and preferably both the upper and lower layers, are comprised of light transmissive amorphous fluoropolymers and the intermediate layer is comprised of a light transmissive material that is a non-elastomeric material, preferably having a glass transition temperature equal to or higher than 0 ℃. Types of 3D printers that may be enhanced in performance through the use of these laminates include, but are not limited to, DLP (digital light projector or digital light processor based 3D printers), DLV (digital light valve based 3D printers), CLIP 3D printers, SLA 3D printers, and other 3D printers.

Some 3D printers operate based on a light source that emits light through a transparent build area (also referred to as a build plate or build assembly), which is typically a transparent area of a tray that holds the resin that will form the part, and the light triggers chemical polymerization in the resin according to the pattern of emitted light. Typically, there is a moving platform (stage) that moves vertically away from the build area while the part is being produced. If the transparent build region has a non-tacky surface, such as a perfluoropolymer, the part will have greatly reduced adhesion to the build region. Furthermore, if the transparent build region is oxygen permeable, for some resins, the polymerization will quench in the narrow region between the part being built and the build region. In this case, the part being built and the build area do not contact and there is no adhesion between the 3D part and the build area. See, for example, US 9,636,873, US10,016,938 and US 9,211,678, the entire contents of which are incorporated herein by reference for all purposes. As described in US 9,636,873, the method is:

"a method of forming a three-dimensional object, the method performed by: (a) Providing a build plate and a build table, the build plate comprising a semipermeable member, the semipermeable member comprising a build surface, wherein the build surface and the build plate define a build region therebetween, and the build surface is in fluid communication with a polymerization inhibitor source through the semipermeable member; (b) Filling the build area with a polymerizable liquid, the polymerizable liquid being in contact with the build surface, (c) irradiating the build area through the build plate to create a solid polymerized area within the build area while forming or maintaining a liquid film release layer comprising the polymerizable liquid formed between the solid polymerized area and the build surface, wherein polymerization of the liquid film is inhibited by a polymerization inhibitor; and (d) advancing the stage with the polymerized region adhered thereto away from the build surface on the build plate to create a subsequent build region between the polymerized region and the build surface while filling the subsequent build region with polymerizable liquid as in step (b).

The use of the exemplary laminates of the present invention in a 3D printer is illustrated by way of example in the following figures.

Referring now to the drawings

Fig. 1 is a section through a part of the laminate of the invention. In FIG. 1, reference numerals denote

11 is a top layer made of an amorphous perfluoropolymer having an oxygen permeability of at least 100 Barrer.

12 is an intermediate layer composed of a material having an oxygen permeability of at least 10Barrer.

13 is a bottom layer composed of an amorphous perfluoropolymer having an oxygen permeability of at least 10Barrer and is the same as or different from the top layer 11.

14A and 14B are intermediate primer layers, each layer having a thickness of, for example, 55-100 nm.

Fig. 2 is an enlarged cross-section of a portion of fig. 1. In FIG. 2, reference numerals denote

11 is the top layer

12 is an intermediate layer

14A is a primer layer between the top layer 11 and the center layer 12

125 denotes the activated surface of the intermediate layer 12. The activated surface may for example have a thickness of 3-20nm

Fig. 3 is a diagrammatic illustration of a 3D printer. In FIG. 3, reference numerals denote

31 is a loading table

32 is a three-dimensional object being produced

33 is a polymerizable liquid for 3D objects

34 is a gradient of polymerization

35 is a dead zone

37 is a polymerization inhibitor

38 is radiation.

Fig. 4 is a diagrammatic illustration of another 3D printer. In FIG. 4, reference numerals denote

Reference numeral 41 denotes a build station

42 is the object being produced

43 is a liquid photopolymerizable resin

44 is a dead zone

45 is a resin cylinder

46 is a window in the resin cylinder

47 is a pattern illuminator

48 is a vertical lead screw driven by a motor 49.

Claims

1. A laminate, comprising

(1) An upper layer (a) transmitting light and (b) being composed of an upper layer polymer composition being a single polymer or a mixture of polymers, at least one of which is a fluoropolymer as defined hereinbefore,

(2) An intermediate layer having a first surface, the intermediate layer (a) adhering to the upper layer, (b) transmitting light and (c) being comprised of an intermediate polymer composition that is a single polymer or a mixture of multiple polymers, and

(3) A lower layer (a) adhered to a second opposite surface of the intermediate layer, (b) transmitting light, (c) being comprised of a lower layer polymer composition, and (D) inhibiting or preventing deformation of the upper layer when the laminate is heated during its use as a window in a 3D printer, the lower layer polymer composition being a single polymer or a mixture of multiple polymers.

2. The laminate according to claim 1, wherein the underlying polymer composition comprises a fluoropolymer as defined hereinbefore.

3. The laminate according to claim 2, wherein the fluoropolymer is tetrafluoroethylene.

4. A laminate according to claim 2 or claim 3, wherein the upper layer composition and the lower layer composition are the same and each composition has an oxygen permeability of at least 100 Barrer.

5. A laminate according to any one of claims 1-3, wherein the intermediate polymer composition comprises a non-elastomeric polymer having a glass transition temperature of at least 0 ℃.

6. A laminate according to any one of claims 1-3, wherein the intermediate polymer composition comprises a PMP polymer as defined hereinbefore.

7. The laminate of any one of the preceding claims, comprising a first primer layer between the upper layer and the intermediate layer and a second primer layer between the intermediate layer and the lower layer.

8. A 3D printer for preparing an article of a desired construction, the apparatus comprising

(2) A window having an upper surface and an opposite lower surface,

(3) Means for delivering the polymer composition onto or adjacent the upper surface of the window, an

(4) Means for projecting a pattern of light onto a lower surface of the window, the pattern corresponding to a part having the desired configuration, and the window being transparent to the light,

whereby, when the device is in operation, the polymeric composition is photopolymerized on or adjacent to the upper surface of the window and forms a part corresponding to the part having the desired configuration;

wherein the window comprises a laminate according to any one of claims 1-6.

9. A method of preparing a laminate according to any one of claims 1-7, the method comprising the steps of:

(A) Providing a film comprised of the intermediate polymer composition, the film having first and second surfaces,

(B) Exposing each of the first and second surfaces of the film to corona etching or plasma etching or both,

(C) A primer solution is applied to each of the first and second surfaces of the film,

(D) Drying the primer solution applied to the first and second surfaces of the film,

(E) Coating the first surface of the film with a solution of the upper polymer composition and allowing or causing the solution to harden

(F) Coating the second surface of the film with a solution of the underlying polymer composition and allowing or causing solution hardening of the underlying polymer composition.

10. A method of preparing a laminate according to any one of claims 1-7, the method comprising the steps of:

(C) Adhering a preformed film comprised of the upper layer polymer composition to the first surface of the film comprised of the intermediate polymer composition,

(D) Adhering a preformed film comprised of the underlying polymer composition to the second surface of the film comprised of the intermediate polymer composition.

11. A method of making the laminate of any one of claims 1-7, the method comprising

(A) Providing an extrusion line capable of separately extruding (1) the upper layer polymer composition, (2) the intermediate polymer composition, and (3) the lower layer polymer composition, and operating the extrusion line to extrude the upper layer polymer composition onto a first surface of the extruded intermediate polymer composition and to extrude the lower layer polymer composition onto an opposite second surface of the extruded intermediate polymer composition.

12. A 3D printer comprising the laminate of any one of claims 1-7.

13. The 3D printer of claim 11, comprising

(2) A window having an upper surface and an opposite lower surface,

(4) Means for protecting a pattern of light onto a lower surface of the window, the pattern corresponding to a part having the desired configuration, and the window being transparent to the light,

wherein the window comprises a laminate according to any one of claims 1-7.

14. A 3D printer according to claim 11 or 12, wherein the window is planar.